Science and technology

Frugal innovation

A flashy solution

READERS familiar with "M.A.S.H.", a popular American television series from the 1970s set during the Korean war, may recall an episode where Hawkeye Pierce, the show's physician protagonist, desperately scratches around for a way to avoid amputating an injured soldier's leg. What he needs is a clamp small enough to hold an artery without crushing it. What he has is a device used for heart surgeries which proves inadequate for the smaller arteries of the leg. Unable to find a suitable replacement in time, he turns to a Korean tinkerer for help. For ten bucks, the man adept at making snuff boxes and fake diamond rings builds a tiny vascular clamp. The improvised device saves a limb.

Ashwin Mallipatna, an eye surgeon at Bangalore's Narayana Nethralaya hospital, and Alefia Merchant, a medical student at University of Montreal, have embraced similarly frugal innovation to tackle a problem which, though perhaps less drastic than Dr Pierce's, is certainly more ubiquitous. An estimated 19m children across the globe suffer from visual impairment. According to the World Health Organisation, 90% of them live in developing countries. Many could be helped if only the problem were diagnosed early enough. It takes a paediatrician less than five minutes to spot an abnormality in a child's eye. Alas, in parts of rural India where villages are situated miles away from any hospital, such tests remain lamentably rare. Dr Mallipatna and Ms Merchant wondered whether they could be made easier by dispensing with the direct ophthalmoscope, a clunky specialist device (invented, incidentally, by this blog's patron), and plumping instead for a simple digital camera.

Dr Mallipatna's technique borrows from the red-eye effect, that scourge of amateur photography. The effect is caused by the camera flash passing through a pupil which is dilated—as it tends to be in darker surroundings when flash is called for—and bouncing off the retina, the eye's light-sensor. The retina is replete with blood vessels and it is their colour that is captured by the camera, whose shutter snaps only after the flash is reflected off them, but before the eye has a chance to adjust to the burst of light by contracting the pupil.

It turns out that any colour other than orange or red suggests a need for immediate medical help. Also, if one eye looks cherry-red while the other is much duller, this asymmetry may hint at a blockage in one eye. Much like the ophthalmoscope, this technique does not identify the cause of the condition, merely the symptoms. Even so, a diagnosis is a boon for children aged one to four years old who might have trouble explaining what ails them. Many might not even realise there is a problem. “If you were born with four fingers, you'd never miss the fifth one,” says Dr Mallipatna.

He stumbled upon the idea during his short stint with Daisy's Eye Cancer Fund, a not-for-profit organisation in Canada. While leafing through a photo album, he noticed that many children diagnosed with eye disease had a red reflex in only one eye. It then hit Dr Mallipatna that a similar phenomenon could be exploited systematically as a diagnostic tool, by employing a compact digital camera.

For their pilot project, Dr Mallipatna and Ms Merchant picked Pavagada, a town situated about 168km (105 miles) from Bangalore. Community nurses trained to detect leprosy, tuberculosis and other chronic diseases patiently listened to Ms Merchant's halting Kannada, the main language used in the area, as she explained how to handle the new medical equipment. “Many had never clicked pictures. They found it hard having to look into the screen, focus and press the button— something that we wouldn't think twice about. But things got better,” Ms Merchant recalls. Over 160 children were screened; Ms Merchant claims that the results were comparable to a direct ophthalmoscope but admits some false positives may have heaped unnecessary stress on worried parents.

Dr Mallipatna and Ms Merchant are up against some deeply entrenched social stigmas which make helping the visually impaired harder than it ought to be. For instance, squinting is often left unattended not to put off Lakshmi, the Goddess of wealth, believed to be partial to those households which have a child with a squint, says Dr Mallipatna. The camera flash itself can be a problem, too. Some villagers see it as an evil eye which visits bad luck on the child and its kin. “It's frustrating," he complains.

The project also faces technical challenges. Paradoxically, technological progress is proving an obstacle. Newer cameras are equipped with anti-red-eye features. Nowadays even cheap devices pre-empt the red reflex by shining a beam onto the subject before the flash goes off. Cameras will only get better, so Dr Mallipanta may need to start hoarding older models.

But Dr Mallipatna and Ms Merchant are optimistic. The plan is to take the project to the masses later this year. The next step will be to join forces with the National Rural Health Mission with a view to making eye screening compulsory, and bundling it with vaccinations. As many as four in five visual impairments can be avoided or cured if detected early enough. Clever ideas and crafty tinkering may make that goal possible to attain.

Readers' comments

Thank you AAK. Brilliant post. Jeez why don't you guys use your names in the by-lines?
I hope at least some of the zillion Indian doctors in the US activate some kind of social-responsibility gene and relocate to India as the techies are starting to do.
The Narayana Hridayalaya (heart-centre), a sister concern of Narayana Netralaya, has made some amazing innovations in bringing down the cost and boosting the reach of cardiac care.
Hopefully the HMOs will look eastward some day.

This article suggests that Dr Mallipanta may need to start hoarding older cameras because the newer devices are equipped with anti-red-eye features... . Dear Economist: In ALL professional cameras, and many consumer models, you can disable the red-eye reduction feature. But to do this you need to read the instruction manual ;)